Cutting Your Cigar

Closely examine the "head" of the cigar -  this is the closed end to be clipped. Most cigars have what is called a "cap" - a bit of tobacco leaf used to close of the end. Inspect the cigar to determine how far down the length of the cigar the cap goes (this is usually 1/4" - 3/8; sometimes less, and on figurado shapes sometimes longer). Where the cap stops is your cutting limit, If you cut beneath this, or even too close, your cigar will start to unravel.

Try to cut as minimally as possible while still opening approximately 75%-85% of the end. This might mean cutting as little as 1/32" down or as much as 3/8" - it depends on the cigar's roll and cap.
When using a guillotine cutter, line up your cigar at eye level and clip it quickly. This method will almost always guarantee satisfactory results

A punch cutter, although this isn't really a cutter, is easy to use, makes a perfect round opening, and negates the problem of how much to clip.

Another option is a V-Cut clipper. Cap length isn't a concern here, as the smoker rests the cigar against the clipper while it takes out a v-notched shaped bit of tobacco of the same size every time.
Cigar scissors are elegant, but difficult to use and hard to carry around. Other methods include razor blades, Swiss Army or pocket knives, or even your teeth. Ultimately, clipping your cigar is a matter of what works best for you.
(www.cigargroup.com)